Abstract
Objective: In neuroendovascular therapy, cases of above-threshold level of radiation-induced skin injuries have been reported. The aim of this study was to evaluate the actual radiation exposure of patients undergoing neurovascular interventional radiology and highlight the problems associated with this approach.
Methods: A multicenter questionnaire survey about the actual radiation exposure in neuroendovascular procedures was posted on the Web site of the Japanese Society of Circulatory Technology. We investigated the procedure time, fluoroscopy time, dose area product, number of frames, and correlations between exposure dose and properties of aneurysms in coil embolization. In addition, we calculated the total entrance skin doses and the crystalline lens doses by using dose area product values.
Results: A total of 285 data sets from 29 medical facilities were evaluated. For the cases, the procedure time, fluoroscopy time, dose area product, and number of frames were as follows (presented as mean±SD values): 190.4±85.0 min, 107.7±60.3 min, 36.5±20.3 mGy · m2, and 1035.8±562.9 frames, respectively. Statistically positive correlations were observed between the dose area product and aneurysm volume, necksize, and number of coils used in embolization of cerebral aneurysm. No significant difference in total skin dose and crystalline lens dose was observed between the ruptured and nonruptured aneurysms. In addition, no difference in procedure time was observed between the single and biplane machines. The total entrance doses to the head skin and crystalline lens on the x-ray tube side were estimated as 3.8±2.1 and 0.91±0.55 Gy, respectively.
Conclusion: We demonstrated the potential occurrence of tissue reactions in neurovascular interventional procedures. In particular, the estimated dose to the crystalline lens exceeded the new threshold level (i.e., 0.5 Gy) in the International Commission on Radiological Protection statement on tissue reaction. To prevent radiation injuries, radiation safety management should be standardized especially in the field of neurointervention.
